diff --git a/dialects/mssql/mssql.go b/dialects/mssql/mssql.go
index a8d3c45a..731721cb 100644
--- a/dialects/mssql/mssql.go
+++ b/dialects/mssql/mssql.go
@@ -1,12 +1,16 @@
 package mssql
 
 import (
+	"database/sql/driver"
+	"encoding/json"
+	"errors"
 	"fmt"
 	"reflect"
 	"strconv"
 	"strings"
 	"time"
 
+	// Importing mssql driver package only in dialect file, otherwide not needed
 	_ "github.com/denisenkom/go-mssqldb"
 	"github.com/jinzhu/gorm"
 )
@@ -201,3 +205,27 @@ func currentDatabaseAndTable(dialect gorm.Dialect, tableName string) (string, st
 	}
 	return dialect.CurrentDatabase(), tableName
 }
+
+// JSON type to support easy handling of JSON data in character table fields
+// using golang json.RawMessage for deferred decoding/encoding
+type JSON struct {
+	json.RawMessage
+}
+
+// Value get value of JSON
+func (j JSON) Value() (driver.Value, error) {
+	if len(j.RawMessage) == 0 {
+		return nil, nil
+	}
+	return j.MarshalJSON()
+}
+
+// Scan scan value into JSON
+func (j *JSON) Scan(value interface{}) error {
+	str, ok := value.(string)
+	if !ok {
+		return errors.New(fmt.Sprint("Failed to unmarshal JSONB value (strcast):", value))
+	}
+	bytes := []byte(str)
+	return json.Unmarshal(bytes, j)
+}
diff --git a/main.go b/main.go
index 25c3a06b..de6ce428 100644
--- a/main.go
+++ b/main.go
@@ -48,6 +48,7 @@ func Open(dialect string, args ...interface{}) (db *DB, err error) {
 	}
 	var source string
 	var dbSQL SQLCommon
+	var ownDbSQL bool
 
 	switch value := args[0].(type) {
 	case string:
@@ -59,8 +60,10 @@ func Open(dialect string, args ...interface{}) (db *DB, err error) {
 			source = args[1].(string)
 		}
 		dbSQL, err = sql.Open(driver, source)
+		ownDbSQL = true
 	case SQLCommon:
 		dbSQL = value
+		ownDbSQL = false
 	default:
 		return nil, fmt.Errorf("invalid database source: %v is not a valid type", value)
 	}
@@ -78,7 +81,7 @@ func Open(dialect string, args ...interface{}) (db *DB, err error) {
 	}
 	// Send a ping to make sure the database connection is alive.
 	if d, ok := dbSQL.(*sql.DB); ok {
-		if err = d.Ping(); err != nil {
+		if err = d.Ping(); err != nil && ownDbSQL {
 			d.Close()
 		}
 	}
@@ -119,7 +122,7 @@ func (s *DB) CommonDB() SQLCommon {
 
 // Dialect get dialect
 func (s *DB) Dialect() Dialect {
-	return s.parent.dialect
+	return s.dialect
 }
 
 // Callback return `Callbacks` container, you could add/change/delete callbacks with it
@@ -484,6 +487,8 @@ func (s *DB) Begin() *DB {
 	if db, ok := c.db.(sqlDb); ok && db != nil {
 		tx, err := db.Begin()
 		c.db = interface{}(tx).(SQLCommon)
+
+		c.dialect.SetDB(c.db)
 		c.AddError(err)
 	} else {
 		c.AddError(ErrCantStartTransaction)
@@ -748,6 +753,7 @@ func (s *DB) clone() *DB {
 		Value:             s.Value,
 		Error:             s.Error,
 		blockGlobalUpdate: s.blockGlobalUpdate,
+		dialect:           newDialect(s.dialect.GetName(), s.db),
 	}
 
 	for key, value := range s.values {
diff --git a/migration_test.go b/migration_test.go
index 7c694485..78555dcc 100644
--- a/migration_test.go
+++ b/migration_test.go
@@ -398,6 +398,53 @@ func TestAutoMigration(t *testing.T) {
 	}
 }
 
+func TestCreateAndAutomigrateTransaction(t *testing.T) {
+	tx := DB.Begin()
+
+	func() {
+		type Bar struct {
+			ID uint
+		}
+		DB.DropTableIfExists(&Bar{})
+
+		if ok := DB.HasTable("bars"); ok {
+			t.Errorf("Table should not exist, but does")
+		}
+
+		if ok := tx.HasTable("bars"); ok {
+			t.Errorf("Table should not exist, but does")
+		}
+	}()
+
+	func() {
+		type Bar struct {
+			Name string
+		}
+		err := tx.CreateTable(&Bar{}).Error
+
+		if err != nil {
+			t.Errorf("Should have been able to create the table, but couldn't: %s", err)
+		}
+
+		if ok := tx.HasTable(&Bar{}); !ok {
+			t.Errorf("The transaction should be able to see the table")
+		}
+	}()
+
+	func() {
+		type Bar struct {
+			Stuff string
+		}
+
+		err := tx.AutoMigrate(&Bar{}).Error
+		if err != nil {
+			t.Errorf("Should have been able to alter the table, but couldn't")
+		}
+	}()
+
+	tx.Rollback()
+}
+
 type MultipleIndexes struct {
 	ID     int64
 	UserID int64  `sql:"unique_index:uix_multipleindexes_user_name,uix_multipleindexes_user_email;index:idx_multipleindexes_user_other"`
diff --git a/query_test.go b/query_test.go
index fac7d4d8..15bf8b3c 100644
--- a/query_test.go
+++ b/query_test.go
@@ -181,17 +181,17 @@ func TestSearchWithPlainSQL(t *testing.T) {
 
 	scopedb.Where("birthday > ?", parseTime("2000-1-1")).Find(&users)
 	if len(users) != 2 {
-		t.Errorf("Should found 2 users's birthday > 2000-1-1, but got %v", len(users))
+		t.Errorf("Should found 2 users' birthday > 2000-1-1, but got %v", len(users))
 	}
 
 	scopedb.Where("birthday > ?", "2002-10-10").Find(&users)
 	if len(users) != 2 {
-		t.Errorf("Should found 2 users's birthday >= 2002-10-10, but got %v", len(users))
+		t.Errorf("Should found 2 users' birthday >= 2002-10-10, but got %v", len(users))
 	}
 
 	scopedb.Where("birthday >= ?", "2010-1-1").Where("birthday < ?", "2020-1-1").Find(&users)
 	if len(users) != 1 {
-		t.Errorf("Should found 1 users's birthday < 2020-1-1 and >= 2010-1-1, but got %v", len(users))
+		t.Errorf("Should found 1 users' birthday < 2020-1-1 and >= 2010-1-1, but got %v", len(users))
 	}
 
 	DB.Where("name in (?)", []string{user1.Name, user2.Name}).Find(&users)
@@ -532,28 +532,28 @@ func TestNot(t *testing.T) {
 	DB.Table("users").Where("name = ?", "user3").Count(&name3Count)
 	DB.Not("name", "user3").Find(&users4)
 	if len(users1)-len(users4) != int(name3Count) {
-		t.Errorf("Should find all users's name not equal 3")
+		t.Errorf("Should find all users' name not equal 3")
 	}
 
 	DB.Not("name = ?", "user3").Find(&users4)
 	if len(users1)-len(users4) != int(name3Count) {
-		t.Errorf("Should find all users's name not equal 3")
+		t.Errorf("Should find all users' name not equal 3")
 	}
 
 	DB.Not("name <> ?", "user3").Find(&users4)
 	if len(users4) != int(name3Count) {
-		t.Errorf("Should find all users's name not equal 3")
+		t.Errorf("Should find all users' name not equal 3")
 	}
 
 	DB.Not(User{Name: "user3"}).Find(&users5)
 
 	if len(users1)-len(users5) != int(name3Count) {
-		t.Errorf("Should find all users's name not equal 3")
+		t.Errorf("Should find all users' name not equal 3")
 	}
 
 	DB.Not(map[string]interface{}{"name": "user3"}).Find(&users6)
 	if len(users1)-len(users6) != int(name3Count) {
-		t.Errorf("Should find all users's name not equal 3")
+		t.Errorf("Should find all users' name not equal 3")
 	}
 
 	DB.Not(map[string]interface{}{"name": "user3", "company_id": nil}).Find(&users7)
@@ -563,14 +563,14 @@ func TestNot(t *testing.T) {
 
 	DB.Not("name", []string{"user3"}).Find(&users8)
 	if len(users1)-len(users8) != int(name3Count) {
-		t.Errorf("Should find all users's name not equal 3")
+		t.Errorf("Should find all users' name not equal 3")
 	}
 
 	var name2Count int64
 	DB.Table("users").Where("name = ?", "user2").Count(&name2Count)
 	DB.Not("name", []string{"user3", "user2"}).Find(&users9)
 	if len(users1)-len(users9) != (int(name3Count) + int(name2Count)) {
-		t.Errorf("Should find all users's name not equal 3")
+		t.Errorf("Should find all users' name not equal 3")
 	}
 }
 
diff --git a/scope.go b/scope.go
index 397ccf0b..a05c1d61 100644
--- a/scope.go
+++ b/scope.go
@@ -63,7 +63,7 @@ func (scope *Scope) SQLDB() SQLCommon {
 
 // Dialect get dialect
 func (scope *Scope) Dialect() Dialect {
-	return scope.db.parent.dialect
+	return scope.db.dialect
 }
 
 // Quote used to quote string to escape them for database
@@ -1216,11 +1216,17 @@ func (scope *Scope) addForeignKey(field string, dest string, onDelete string, on
 
 func (scope *Scope) removeForeignKey(field string, dest string) {
 	keyName := scope.Dialect().BuildKeyName(scope.TableName(), field, dest, "foreign")
-
 	if !scope.Dialect().HasForeignKey(scope.TableName(), keyName) {
 		return
 	}
-	var query = `ALTER TABLE %s DROP CONSTRAINT %s;`
+	var mysql mysql
+	var query string
+	if scope.Dialect().GetName() == mysql.GetName() {
+		query = `ALTER TABLE %s DROP FOREIGN KEY %s;`
+	} else {
+		query = `ALTER TABLE %s DROP CONSTRAINT %s;`
+	}
+
 	scope.Raw(fmt.Sprintf(query, scope.QuotedTableName(), scope.quoteIfPossible(keyName))).Exec()
 }